Crown

Board: Porsche - 911 - 997 Language: English Region: Worldwide Share/Save/Bookmark Close

Forum - Thread


    Re: Settle office argument: car swerves: do what?

    Quote:
    MMD said:
    If you put the brakes on the car will obviously ONLY use ABS to control wheels rotation to try to regain control. Put brakes on and ZERO power will be applied to any wheel(s)?



    As a clarification, ESP selectively applies brakeforce on a particular wheel (outer front wheel for oversteer, inner rear wheel for understeer) to prevent the car from spinning. Due to dynamic load distribution, the inner rear wheel has the lowest amount of weight transferred in cornering (excluding the influence of acceleration), therefore it is much more difficult to diminish understeer. As I mentioned above, this can only work with sufficient friction provided. Hence my above stated question reg. engaged transmission. Further bear in mind that Porsche's ESP system, while being deactivated, reengages under heavy braking.
    There are only a few cars that use selective torque application to support this, e.g. the Mitsubishi Lancer with an active rear differential.

    Re: Settle office argument: car swerves: do what?

    Quote:
    Leawood911 said:
    Quote:
    ADias said:
    Quote:
    MMD said:...

    Sounds crazy? Is this what's happening though?...



    No. It's far more sophisticated than that. The system uses a variety of sensors (2-axis accelerometers, yaw sensor and path information) to do its job. It's more than a simple closed-loop design, it also uses predictive coding and other stuff. It just works!

    And... please do not fret about it. Let the system work by keeping PSM on and on your side, do not make stupid mistakes.



    Fine I take it all back. I did not want to cause anyone to wreck their car. My advice was meant for people who know how to control a car and who are driving in good weather conditions.

    I drive all year around in my 911 and while I do like ABS I still turn off PSM in almost all conditions unless I forget. There is a good reason why racers and pros want a way to disable PSM in cars they drive.

    I guess if you have never been able to control a car without all that intervention then you need to use it, especially in bad weather. For me it jumps in split seconds AFTER I have decided and implemented the correct plan of action and it hinders my control. It just pisses me off to that extent. Then again I am not foolish enought to drive past the limits of the car and the conditions in the first place except when I want to push the envelope.

    It's OK if you consider my advice poor. I would prefer people make up their own minds. All I can say is I have driven 911 Porsches since I was 15 (now 43) and I have at least 700,000 miles behind the wheel of these cars. PSM is just too slow for me and taking away my throttle is never welcome.

    The best piece of advice I can give is to PASS ON THE LEFT, DRIVE ON THE RIGHT and USE TURN SIGNALS for every more you make.

    I bet many of the folks giving 'driving' advice here don't even bother to signal, or drive in the correct lane. I was shocked, during the recent NorthEast drive I attended, how infrequently the other Porsche drivers signaled and how often they passed on the right, recklessly! Incredible. Do we need DE to learn right of way rules and how to signal?

    Cheers, and drive safe.




    not to be taken personally but this is the biggest bull i have ever read. unless you are on a track or closed private road, please, do keep PSM ON. i would not want to be struck by your car when you loose control...

    i guess when riding a motorbike, you would not want to wear a helmet as you do not know what effect it would have to the impact of your skull with the tarmac

    turning PSM off while commuting on public roads is not a thing of bravery or skill. its simply an aid to make it easier and safer for all of us.

    Re: Settle office argument: car swerves: do what?

    Quote:
    intouch1 said:


    not to be taken personally but this is the biggest bull i have ever read. unless you are on a track or closed private road, please, do keep PSM ON. i would not want to be struck by your car when you loose control...

    i guess when riding a motorbike, you would not want to wear a helmet as you do not know what effect it would have to the impact of your skull with the tarmac

    turning PSM off while commuting on public roads is not a thing of bravery or skill. its simply an aid to make it easier and safer for all of us.



    Please don't take this personally but...
    maybe you should read what I wrote again. If you like PSM then use it. I agree that anyone who is not comfortable with the performance of a car or the weather conditions can benefit from having it. For me, I think it reacts too slow. As my car starts to slide I can make the perfect correction and then all of a sudden, half way though the turn I lose throttle control and braking at the corners starts out of the blue. Last time this happened I was practically at a standstill in the middle of an intersection when PSM was done screwing with me. I thought the car stalled! That is what I do not like and that is why for me it is not ideal or quick enough FOR ME. Maybe my Mom would like it in the winter.

    On the other hand, I do like PASM since it is more transparent and quicker to react. It does help lap times too.

    The bottom line is that PSM senses any excessive input and assumes you are in trouble and quickly tries to save you even if you don't need or want it. That is a problem if you are not really in trouble and just trying to move quickly. Also, if you are a poor driver it may save you a couple of times, giving you a false sense of security (and of your actual skill level). In the end it can not defeat physics so it is then just a matter of time until you buy the next lightpole.

    Rest assured that you don't have to worry about me losing control and hitting you because I am not that type of driver on the street or on the track. I bet I have driven on more ICE and snow in a 911 than you have (please don't take the lack of snow in Egypt personally), and most of it in old Porsches that did not even have ABS.

    Your assertion, that turning off PSM on a public road is endangering those around me, is a the funniest thing I have ever heard. Like it's up there with drunk driving or something.

    Speeding, not signaling, not obeying traffic laws - these are the real transgressions which cause accidents. Turning of PSM and then controling the car 'manually' is no more dangerous than driving without the cruise control on the highway unless you are driving like a maniac (it takes a lot to get a 997 to spin). The fact is that responsibility to control your car is yours with or without PSM. Always drive like lives around you depend on your judgement and car control. PSM or no PSM is no excuse for losing control - ever. And, if you think you are not safe without PSM then you are not safe with it.

    What's next, mandatory PSM on every car? How about just limiting us all to 65mph?

    By the way, I wear a full face helmet when riding my 49cc scooter and there is no helmet law in Kansas.

    Answer this - while you are driving with PSM on to save all those around from your overpowered, out-of-control sports car do you signal and obey all other traffic laws? I would be much more worried about the lack of a turn signal than the little PSM light being on or off. That is a much more accurate indicator of being a serious driver concerned about those around you.
    Cheers,

    Re: Settle office argument: car swerves: do what?

    Settle an office argument? MMD with all your posts you have an office too? How do you find the time?

    Re: Settle office argument: car swerves: do what?

    Quote:
    Over the Hill said:
    Settle an office argument? MMD with all your posts you have an office too? How do you find the time?



    I run the joint and, as an amusing reference, like George Costanza on Seinfeld I always look annoyed. Made George look bizzy.

    Re: Settle office argument: car swerves: do what?

    Quote:
    MMD said:
    Also ALWAYS signal when you are getting back in lane after passing. This means even though you took a risk (probably perceived as significant by elderly or nervous drivers) you still have respect and courtesy for the driver you passed.



    Great advice! Best to show folks that Porsche owners are a cut above most (if not almost all) others, even if we are passing them extremely quickly (to say the least).

    Jim

    Re: Settle office argument: car swerves: do what?

    Definitely!

    Re passing on the right... I think that if you never pass left car lanes on the right lane, you will never pass, as lane speed hierarchy is a thing of the past, especially in California.

    Re: Settle office argument: car swerves: do what?

    Sad to say that in the United States this is too often true. It's a dangerous maneuver, and when I'm in my 911S, I am very careful when I do it, which is not often. But you are correct in that you pass more infrequently because too many people plant themselves in the left lane and then stay there, whether or not they are actually passing other cars in a reasonably quick manner.

    Jim

    Re: Settle office argument: car swerves: do what?

    Lane hierarchy and correction of tail-gating bad habit should be part of an educational driving campaign, perhaps by someone like AAA.

    Re: Settle office argument: car swerves: do what?

    Quote:
    MMD said:
    Ever notice this: if you gas the car going straight (just normal driving) and then touch the brake the throttle is closed, IOW, just touch the brake pedal when you're driving normally and the gas pedal becomes inactive.

    So if you are in a swerving situation and you apply gas isn't it reasonable that the car will cut the throttle or apply throttle to power whichever wheel(s) necessary since it is trying to recover?

    Since you are gassing the car it will know you don't want to stop and so will give you enough power (or brakes) to whichever wheels (especially on 4 WD) to keep you going where you are steering?

    Does it also make sense that if you take your foot off the gas totally the car thinks you want to STOP and will not do anything to power any wheel(s) to get you on track?

    If you put the brakes on the car will obviously ONLY use ABS to control wheels rotation to try to regain control. Put brakes on and ZERO power will be applied to any wheel(s)?

    IOW, if you remove foot from gas (or put on brake?) the car will only use ABS to stop car. OTOH, if you give the car gas it will use whatever amount of throttle it needs to _power_ whichever wheels need power to get you where you are steering?

    It's like there are TWO drivers, us and the PSM. If you give indications you need to stop it will brake car only. If you give indications you need to keep driving it will, judiciously, add power (and/or brakes) to whichever wheels need it to keep you in motion as you try to steer toward recovery?

    Sounds crazy? Is this what's happening though?

    If this is so, it seems you should almost NEVER _completely_ take your foot off the gas (unless you are going to slam into something, then use brakes and steer as you pray).

    Seems logical to me but why should logic play a part?



    This is one of the most confusing posts I've ver read. I have really no idea what you are saying.

    I have not noticed that the throttle becomes unresponsive when the brake is applied, nor does that make any sense. I have, during emergency braking when brake and clutch were all the way in, accidentally also depressed the gas (because my right foot was mashing the brake so quickly and it overlapped with the gas pedal) and I can tell you with certainty that the throttle revved up to 5000 RPM - clearly not unresponsive.

    If you are swerving, as long as the car is travelling in the direction the steering wheel is pointing, regardless of what you are doing with gas and brake, PSM will not intervene. If you are swerving and the car is not going in the direction that the wheel is pointing, PSM will intervene (though not immediately - it takes a fraction of a second) to "right" the car.

    PSM is incredible. Unless you are trying to slide the car, bleieve me, you want it on.

    Even on the track, when it intervenes, it does so because you made a mistake, and as has already been posted (by someone who routinely turns it off), it improves lap times (because it keeps you on your line instead of sliding all over the place). A moderately experienced driver who gets a time of X on a track in a 997S who then gets into a GT3 will either lose control of the GT3 or get a slower lap time until their driving improves, and the reason is PSM.

    This is very nicely illustrated at the Porsche Sport Driving School on a super slick track where you are timed to perform 4 laps around a figure 8 circuit. Almost everybody gets MUCH faster times with PSM on. The few people who are faster with PSM off are the very good drivers.

    I would not try to out-think PSM. If you want to slide, or if you have enough experience in high speed spins and slides that you can prevent/minimize them or quickly regain control, as I said, leave it on.

    Re: Settle office argument: car swerves: do what?

    Quote:
    Silver Bullet said:
    Quote:
    MMD said:
    Ever notice this: if you gas the car going straight (just normal driving) and then touch the brake the throttle is closed, IOW, just touch the brake pedal when you're driving normally and the gas pedal becomes inactive.



    This is one of the most confusing posts I've ver read. I have really no idea what you are saying.

    I have not noticed that the throttle becomes unresponsive when the brake is applied, nor does that make any sense.



    You've obviously never tried it!

    If you left foot brake, keeping your right foot on the throttle, then MMD is correct - the throttle becomes noticably inactive.

    Re: Settle office argument: car swerves: do what?

    Quote:
    Silver Bullet said:


    This is one of the most confusing posts I've ver read. I have really no idea what you are saying.

    I have not noticed that the throttle becomes unresponsive when the brake is applied, nor does that make any sense. I have, during emergency braking when brake and clutch were all the way in, accidentally also depressed the gas (because my right foot was mashing the brake so quickly and it overlapped with the gas pedal) and I can tell you with certainty that the throttle revved up to 5000 RPM - clearly not unresponsive.

    If you are swerving, as long as the car is travelling in the direction the steering wheel is pointing, regardless of what you are doing with gas and brake, PSM will not intervene. If you are swerving and the car is not going in the direction that the wheel is pointing, PSM will intervene (though not immediately - it takes a fraction of a second) to "right" the car.





    Sorry, you're probably right..., lemme try to simplify.

    You have TMS (Traction Managment System) and you have PSM on the Turbo.

    If you are headed toward a wall then it's simple: hit the brakes.

    In the following cases you are steering back and forth with the swerve trying to stay pointed on the road while applying gas, applying brake, or no brake and no gas:

    If you are on a road or a track you might decide to _drive_ and steer your way out of the swerve by keeping your foot on the gas and letting TMS and PSM work to try to get the car to where you are steering.

    If you steer back and forth in the swerve to stay on the road _by_rolling_to_a_stop_ and take your foot off the gas, and keep it off the brake, what happens? Does the car "throttle up" as needed? Does it apply brakes as needed? Does TMS work as needed?

    If you steer back and forth into the swerve while hitting the brakes _intending_to_stop_, what happens? Does the car throttle up as needed? Does it hit the brakes as needed? (yes!). Does TMS do it's thing?

    My theory is to keep foot _at least slightly_ on the gas and computer will know you intend to drive and will help you drive by using all systems to stabilize your Turbo.

    Take foot off gas and just steer which systems come into play? Seems like engine will not "throttle up" because there's no foot on the gas.

    Put brakes on and steer back and forth into swerve: is it true that the car thinks you want to stop ASAP and will NOT use any engine power to re-establish traction and keep car pointed where you're steering it?

    Which is the best thing you could do?

    1. keep foot on gas because it's telling engine you intend to drive and you want it to stay involved and power the efforts to re-establish traction.

    2. put foot on brake because it's telling car you want to stop (no engine involvement).

    3. feet off both pedals and just steer car where you want it. Since, given that quirk that brake cancels gas, presumably engine power is NOT cut and will participate in tryin to regain traction.

    What happened to PSM on "standard" 997's?

    Now I'm REALLY confused! My 997 has PSM and no TMS that I'm aware of. Which parallel universe is your stuff coming from?

    Re: What happened to PSM on "standard" 997's?

    Quote:
    Le Chef said:
    Now I'm REALLY confused! My 997 has PSM and no TMS that I'm aware of. Which parallel universe is your stuff coming from?



    LOL.

    Sorry.

    Turbo has Traction Management System.

    C4 has some form of it too.


    C2 will power rear wheels as needed so it's got 1/2 TMS, right?

    Re: Settle office argument: car swerves: do what?

    Quote:
    MMD said:
    Quote:
    Silver Bullet said:


    This is one of the most confusing posts I've ver read. I have really no idea what you are saying.

    I have not noticed that the throttle becomes unresponsive when the brake is applied, nor does that make any sense. I have, during emergency braking when brake and clutch were all the way in, accidentally also depressed the gas (because my right foot was mashing the brake so quickly and it overlapped with the gas pedal) and I can tell you with certainty that the throttle revved up to 5000 RPM - clearly not unresponsive.

    If you are swerving, as long as the car is travelling in the direction the steering wheel is pointing, regardless of what you are doing with gas and brake, PSM will not intervene. If you are swerving and the car is not going in the direction that the wheel is pointing, PSM will intervene (though not immediately - it takes a fraction of a second) to "right" the car.





    Sorry, you're probably right..., lemme try to simplify.

    You have TMS (Traction Managment System) and you have PSM on the Turbo.

    If you are headed toward a wall then it's simple: hit the brakes.

    In the following cases you are steering back and forth with the swerve trying to stay pointed on the road while applying gas, applying brake, or no brake and no gas:

    If you are on a road or a track you might decide to _drive_ and steer your way out of the swerve by keeping your foot on the gas and letting TMS and PSM work to try to get the car to where you are steering.

    If you steer back and forth in the swerve to stay on the road _by_rolling_to_a_stop_ and take your foot off the gas, and keep it off the brake, what happens? Does the car "throttle up" as needed? Does it apply brakes as needed? Does TMS work as needed?

    If you steer back and forth into the swerve while hitting the brakes _intending_to_stop_, what happens? Does the car throttle up as needed? Does it hit the brakes as needed? (yes!). Does TMS do it's thing?

    My theory is to keep foot _at least slightly_ on the gas and computer will know you intend to drive and will help you drive by using all systems to stabilize your Turbo.

    Take foot off gas and just steer which systems come into play? Seems like engine will not "throttle up" because there's no foot on the gas.

    Put brakes on and steer back and forth into swerve: is it true that the car thinks you want to stop ASAP and will NOT use any engine power to re-establish traction and keep car pointed where you're steering it?

    Which is the best thing you could do?

    1. keep foot on gas because it's telling engine you intend to drive and you want it to stay involved and power the efforts to re-establish traction.

    2. put foot on brake because it's telling car you want to stop (no engine involvement).

    3. feet off both pedals and just steer car where you want it. Since, given that quirk that brake cancels gas, presumably engine power is NOT cut and will participate in tryin to regain traction.



    OK - I understand more clearly now, and I don't think I know the answer, but here's what I'm thinking at the moment.

    If the car is understeering, the answer is less throttle, whether you do it or PSM.

    If the car is oversteering, the answer may be complicated, but I think that PSM can probably deal with it most of the time by either cutting back throttle (in the case of power oversteer) or braking individual wheels (as might be the case in lift off oversteer). I'm not sure about that last part, but I believe it to be true, and I believe that I've actually experienced it myself (though its hard to be sure because these things happen so darn fast).

    Thus, I don't think it's an issue if PSM cannot "throttle up".

    I would not try to over think this or out smart PSM: as I wrote, these things happen very very quickly. PSM works very very quickly. PSM also works very very well at keeping one from losing control of the car.

    In a panic situation, my best advice is to ease off the throttle and try to steer the car back on course. If the car starts to spin uncontrollably, then hard on brake and clutch.

    Re: Settle office argument: car swerves: do what?

    Quote:
    Silver Bullet said:


    I would not try to over think this or out smart PSM: as I wrote, these things happen very very quickly. PSM works very very quickly. PSM also works very very well at keeping one from losing control of the car.

    In a panic situation, my best advice is to ease off the throttle and try to steer the car back on course. If the car starts to spin uncontrollably, then hard on brake and clutch.



    Thanks Buddy The last two sentences are particularly helpful. This thread convinced me I have to _make_ time for the PDE in Birmingham.

    Re: Settle office argument: car swerves: do what?

    Earlier, I wrote that throttle lift induced oversteer could probably be corrected by PSM braking individual wheels (rather than throttling back up).

    I'm quite sure that's true, as I experienced it on the track tonight.

    On my warm up lap, with cool tires, I took a sharp left turn a little too quickly in a part of the track where speed has to be scrubbed off. I turned and lifted my foot off the gas and the back end slowly came out. As I counter steered slightly, I thought the tires would grip & it would come back, but it didnt't - it just kept slowly drifting out. Without my foot on the gas at all, eventually (and I was surprised by how long this went on for) PSM intervened: there was a little chirp from braking and a little yellow flash on the dash, and the back end came right in.

    In retrospect, I was enjoying the drift and it never felt out of control at all, so I kind of wish I had been in sport mode at that time. Nonetheless, its yet another time that PSM quickly "righted" the car.

    I would like to understand better exactly how braking a certain wheel can correct that . . .

    Re: Settle office argument: car swerves: do what?

    Assuming a right turn with rear end coming out how about braking the outside (driver's) front wheel? Wouldn't that help force the rear end back in? Just a blind guess on my part.

    Re: Settle office argument: car swerves: do what?

    - Slowly back off throttle while dragging the brakes
    - Counter steer
    - Pray

     
    Edit

    Forum

    Board Subject Last post Rating Views Replies
    Porsche Sticky SUN'S LAST RUN TO WILSON, WY - 991 C2S CAB LIFE, END OF AN ERA (Part II) 3/28/24 3:21 AM
    watt
    689176 1780
    Porsche Sticky Welcome to Rennteam: Cars and Coffee... (photos) 2/19/24 11:51 PM
    Wonderbar
    409013 564
    Porsche Sticky OFFICIAL: Cayman GT4 RS (2021) 5/12/23 12:11 PM
    W8MM
    255665 288
    Porsche Sticky OFFICIAL: Porsche 911 (992) GT3 RS - 2022 3/12/24 8:28 AM
    DJM48
    234912 323
    Porsche Sticky The new Macan: the first all-electric SUV from Porsche 1/30/24 9:18 AM
    RCA
    65485 45
    Porsche Sticky OFFICIAL: Taycan 2024 Facelift 3/15/24 1:23 PM
    CGX car nut
    4642 50
    Porsche The moment I've been waiting for... 2/1/24 7:01 PM
    Pilot
     
     
     
     
     
    857833 1364
    Porsche 992 GT3 7/23/23 7:01 PM
    Grant
    773814 3868
    Porsche OFFICIAL: New Porsche 911 Turbo S (2020) 4/6/23 7:43 AM
    crayphile
    447816 1276
    Porsche Welcome to the new Taycan Forum! 2/10/24 4:43 PM
    nberry
    378813 1526
    Porsche GT4RS 2/22/24 5:16 AM
    tso
    365558 1424
    Porsche Donor vehicle for Singer Vehicle Design 7/3/23 12:30 PM
    Porker
    360747 797
    Others Tesla 2 the new thread 12/13/23 2:48 PM
    CGX car nut
    354667 2401
    Lambo Aventador and SV 3/30/23 1:59 PM
    CGX car nut
    279093 724
    Ferrari Ferrari 812 Superfast 4/21/23 8:09 AM
    the-missile
    275471 550
    Porsche Red Nipples 991.2 GT3 Touring on tour 3/14/24 8:55 PM
    blueflame
    272484 658
    Porsche Collected my 997 GTS today 10/19/23 7:06 PM
    CGX car nut
     
     
     
     
     
    248200 812
    Lambo Huracán EVO STO 7/30/23 6:59 PM
    mcdelaug
    225033 346
    Others Corvette C8 10/16/23 3:24 PM
    Enmanuel
    217899 488
    Lotus Lotus Emira 6/25/23 2:53 PM
    Enmanuel
    196671 101
    Others Gordon Murray - T.50 11/22/23 10:27 AM
    mcdelaug
    155297 387
    Porsche Back to basics - 996 GT3 RS 6/11/23 5:13 PM
    CGX car nut
    126873 144
    Ferrari [2022] Ferrari Purosangue (SUV) 4/15/23 5:20 AM
    watt
    120454 141
    BMW M 2024 BMW M3 CS Official Now 12/29/23 9:04 AM
    RCA
    105949 303
    Motor Sp. 2023 Formula One 12/19/23 5:38 AM
    WhoopsyM
    102498 685
    Others Valkyrie final design? 4/28/23 2:45 AM
    Rossi
    97639 219
    Porsche 2022 992 Safari Model 3/7/24 4:22 PM
    WhoopsyM
    81035 239
    AMG Mercedes-Benz W124 500E aka Porsche typ 2758 2/23/24 10:03 PM
    blueflame
    74331 297
    Porsche 992 GT3 RS 3/3/24 7:22 PM
    WhoopsyM
    52112 314
    Motor Sp. Porsche 963 3/16/24 9:27 PM
    WhoopsyM
    23091 237
    133 items found, displaying 1 to 30.